1. Field of the Invention
The present invention relates to an apparatus and method for reducing moments of a reversible steering axle while substantially increasing ground clearance and strength of the reversible steering axle. The reversible steering axle is typically employed in heavy duty off-road vehicles.
2. Description of the Background Art
The conventional art of FIG. 13 is a schematic of a standard U-shaped steering axle 10 which includes kingpin bore cylinders 12. The kingpin bore cylinders 12 support a kingpin (not shown) that connects a steering knuckle (not shown) to the steering axle 10. In off-road environments, the steering axle 10 is subjected to large forces that interact with the kingpin bore cylinders 12 of the steering axle 10. The forces, in turn, create moments which place the steering axle 10 under tremendous stress.
The conventional steering axle 10 does not permit a vehicle to travel over substantially rough terrains due to low ground clearance C between the conventional steering axle 10 and the ground G. The steering axle 10 of the conventional art is subjected to moments M1 and M2.sub.1, M2.sub.2 that are created by forces F1 and F2 and their respective perpendicular distances X1 and X2. The perpendicular distances X1 and X2 define the spacing between the forces and their respective rotational axes R1, or R2.sub.1, R2.sub.2. Due to the substantial magnitude of forces F1, F2 generated in an off-road environment and due to the significant distance between the rotational axes and these forces, large torsional stress M1 and bending M2.sub.1, M2.sub.2 are produced.
An additional drawback of the conventional art steering axle 10 is the reversibility of such an axle. Reversibility of an axle defines whether a steering axle is capable of being used in two or more types of vehicles. In particular, such a reversibility feature is desirable when the steering axle can be used in two or more distinct types of vehicles made by different manufacturers. The conventional art in FIG. 14 illustrates kingpin bore cylinders 12 which include a first projecting stop 14 and a second projecting stop 16 which are mounted or formed on either side of a kingpin bore cylinder 12.
The first stop 14 is spaced from a top surface of kingpin bore cylinder 12 by a predetermined distance dl while stop 16 is spaced from the top surface of kingpin bore cylinder 12 by a second predetermined distance d2. In the conventional art, distances d1 and d2 are substantially equal. The projecting stops 14, 16 are designed to interact with a stop bolt (not shown) that is attached to a steering knuckle (not shown). In different types of vehicles, the stop bolts interact at distances which are smaller or greater than the first and second distances d1, d2 illustrated in the conventional art. Since both the first and second stops 14, 16 are disposed at the same predetermined distance from the top surface of the kingpin bore cylinder, the conventional steering axle 10 can only be employed in vehicles which have a stop pin at one predetermined location or distance from a steering knuckle. This design does not permit the conventional steering axle 10 to be mounted on different vehicles.
Accordingly, a need in the art exists for a method and an apparatus for substantially reducing moments of a steering axle while substantially increasing ground clearance and strength thereof. Further, a need in the art exists for a method and apparatus for increasing the reversibility of a steering axle so that the axle can be employed with numerous types of vehicles with out substantial retrofitting or increased manufacturing steps of the steering axle.